// This injects a box into the page that moves with the mouse;
// Useful for debugging
(function () {
    const box = document.createElement('div');
    box.classList.add('mouse-helper');
    const styleElement = document.createElement('style');
    styleElement.innerHTML = `
  .mouse-helper {
    pointer-events: none;
    position: absolute;
    top: 0;
    left: 0;
    width: 20px;
    height: 20px;
    background: rgba(0,0,0,.4);
    border: 1px solid white;
    border-radius: 10px;
    margin-left: -10px;
    margin-top: -10px;
    transition: background .2s, border-radius .2s, border-color .2s;
  }
  .mouse-helper.button-1 {
    transition: none;
    background: rgba(0,0,0,0.9);
  }
  .mouse-helper.button-2 {
    transition: none;
    border-color: rgba(0,0,255,0.9);
  }
  .mouse-helper.button-3 {
    transition: none;
    border-radius: 4px;
  }
  .mouse-helper.button-4 {
    transition: none;
    border-color: rgba(255,0,0,0.9);
  }
  .mouse-helper.button-5 {
    transition: none;
    border-color: rgba(0,255,0,0.9);
  }
  `;
    document.head.appendChild(styleElement);
    document.body.appendChild(box);
    document.addEventListener(
        'mousemove',
        (event) => {
            box.style.left = event.pageX + 'px';
            box.style.top = event.pageY + 'px';
            updateButtons(event.buttons);
        },
        true
    );
    document.addEventListener(
        'mousedown',
        (event) => {
            updateButtons(event.buttons);
            box.classList.add('button-' + event.which);
        },
        true
    );
    document.addEventListener(
        'mouseup',
        (event) => {
            updateButtons(event.buttons);
            box.classList.remove('button-' + event.which);
        },
        true
    );
    function updateButtons(buttons) {
        for (let i = 0; i < 5; i++)
        {box.classList.toggle('button-' + i, buttons & (1 << i));}
    }
})();
